• 한국미생물·생명공학회지
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• 제24권1호
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• pp.82-86
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• 1996

Three thousand microbial strains collected from different sources were screened for herbicidal activity. A strain of ME-9189 showed herbicidal activity against Digitaria sanguinalis and Portulaca oleracea was isolated from a mountainy soil. Based on taxonomic studies, the strain was identified as Streptomyces tubercidicus. The active compound of ME-9189 was purified from the culture broth by charcoal, silica gel, sephadex LH-20 column chromatography and crystalization, consecutively. The ME-9189 compound was identified as tubercidin by spectroscopic methods of UV, $^{1}H$ and $^{13}C$-NMR, and EIMS. In the bioassay, growth of radish shoot and root was inhibited by 50% with tubercidin treatment of 10 ppm, showing 2 times higher activity than that of herbicidin A and similar to that of toyocamycin.

• 대한화학회지
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• 제19권6호
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• pp.438-442
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• 1975

Unusual pyrimidine nucleoside인 5-fluoro-4'-thiouridine과 5-Chloro-4'-thiouridine을 5-fluoro-와 5-chlorouracil의 2,4-bis(trimethylsilyl) 유도체들을 만든후, 축합반응하여 합성하였다. Leukemia 1210 cell과 Streptococcus faecium에 대한 기초 생물화학적인 예비시험에 의하면 5-fluoro-4'-thiouridine은 5-fluorouridine보다 억제효과가 월등하여 항암제로서의 전망여하는 앞으로의 임상 화학적인 결과로 구명될것 이라고 예상된다.

• BMB Reports
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• 제41권9호
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• pp.645-650
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• 2008

Nucleoside diphosphate kinase (NDPK) is involved in multiple signaling pathways in mammalian systems, including G-protein signaling. Arabidopsis NDPK2, like its mammalian counterparts, is multifunctional despite its initial discovery phytochrome-interacting protein. This similarity raises the possibility that NDPK2 may play a role in G-protein signaling in plants. In the present study, we explore the potential relationship between NDPK2 and the small G proteins, Pra2 and Pra3, as well as the heterotrimeric G protein, GPA1. We report a physical interaction between NDPK2 and these small G proteins, and demonstrate that NDPK2 can stimulate their GTPase activities. Our results suggest that NDPK2 acts as a GTPase-activating protein for small G proteins in plants. We propose that NDPK2 might be a missing link between the phytochrome-mediated light signaling and G protein-mediated signaling.

• Annals of Clinical Neurophysiology
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• 제19권1호
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• pp.40-45
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• 2017

Background: Telbivudine is a nucleoside analogue used for the treatment of chronic hepatitis B, but it often develops mitochondrial toxicity leading to symptomatic myopathy. In this study, three patients with telbivudine induced myopathy were enrolled in order to investigate the nature and pathogenesis of mitochondrial toxicity caused by long-term use of telbivudine. Methods: Clinical features, laboratory findings, muscle pathology, and quantitation of mitochondrial DNA were studied in three patients. Results: Patients presented with progressive muscle weakness with high serum creatine kinase levels. Light microscopic findings of muscle pathology showed ragged red fibers that reacted strongly with succinate dehydrogenase stain, but negative for cytochrome c oxidase activities. Electron microscopy revealed abnormal mitochondrial accumulation with rod shaped inclusions. The quantitative peroxidase chain reaction showed a depletion of mitochondrial DNA in skeletal muscle of the patients. Conclusions: Nucleoside analogues including telbivudine are potent inhibitors of viral DNA polymerases. However, they are not specific for viral DNA and can disturb mitochondrial replication at the same time. All nucleotide analogues should be used with close clinical observation in order to avoid development of mitochondrial myopathy.

• Molecules and Cells
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• 제21권3호
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• pp.330-336
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• 2006

Since its identification in 1989, hepatitis C virus has been the subject of extensive research. The biology of the virus and the development of antiviral drugs are closely related. The RNA polymerase activity of nonstructural protein 5B was first demonstrated in 1996. NS5B is believed to localize to the perinuclear region, forming a replicase complex with other viral proteins. It has a typical polymerase structure with thumb, palm, and finger domains encircling the active site. A de novo replication initiation mechanism has been suggested. To date, many small molecule inhibitors are known including nucleoside analogues, non-nucleoside analogues, and pyrophosphate mimics. NS5B interacts with other viral proteins such as core, NS3, 4A, 4B, and 5A. The helicase activity of NS3 seems necessary for RNA strand unwinding during replication, with other nonstructural proteins performing modulatory roles. Cellular proteins interacting with NS5B include VAMP-associated proteins, heIF4AII, hPLIC1, nucleolin, PRK2, ${\alpha}$-actinin, and p68 helicase. The interactions of NS5B with these proteins might play roles in cellular trafficking, signal transduction, and RNA polymerization, as well as the regulation of replication/translation processes.

• Archives of Pharmacal Research
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• 제17권6호
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• pp.480-482
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• 1994

A number of 5-substituted pyrimidine acyclic nucleosides were synthesized and tested for invitor cytotoxicity against four cell lines (j-82 cell, p-388 cell, FM-3A cell and U-938 cell lines). Synthesis of 1-cyanomethyl-5-substituted pyrimidines (1a-e) and 1-(4-cyanobutyl)-5-substituted pyrimidines (2a-e) was acomplished from the series of alkylation reactions ofl 5-substituted uracils with the corresponding chloacetonitrile and 5-chlorovaleronitile in DMSO under $50^{\circ}C$ temperature. These 5-substituted pyrimidine acylic nucleosides (1a-e and 2a-e) exhibited moderate to significant acitivity aginst four cell lines.

• 대한화학회지
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• 제19권2호
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• pp.130-133
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• 1975

와 5-iodo-pyrimidine nucleoside 의 4'-thio 유도체들은 2,3,5-tri-O-aceytl-4-thio-D-ribofuranosyl chloride 와 5-halogeno-2,4-bis(trimethylsiloxy)pyrimidine의 chloromercury 유도체를 축합시킨후 보호작용기를 제거함으로써 합성하였다. 4'-Thio 유도체들의 생물학적 활성도는 예비시험에서는 이에 대응하는 4'-oxygen 유도체들과 큰 차이가 나지 않지만 4'-thio유도체가 비교적 더높은 활성을 가진다는 사실은 흥미로운 일이며 앞으로 생화학적인 고찰을 계속하는 것은 가치있는 일임을 보여주고 있다.

• 한국자기공명학회논문지
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• 제21권2호
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• pp.50-54
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• 2017

Cupin-superfamily proteins represent the most functionally diverse groups of proteins and include a huge number of functionally uncharacterized proteins. Recently, YaiE, a cupin protein from Escherichia coli has been suggested to be involved in a novel activity of pyrimidine/purine nucleoside phosphorylase (PPNP). In the present study, we achieved a complete backbone NMR assignments of YaiE, by a series of heteronuclear multidimensional NMR experiments on its [$^{13}C/^{15}N$]-enriched sample. Subsequently, secondary structure analysis using the assigned chemical shift values identified 10 obvious ${\beta}-strands$ and a tentative $3_{10}-helix$. Taken all together, the results constitute the first structural characterization of a putative PPNP cupin protein.

• 대한핵의학회지
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• 제30권3호
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• pp.344-350
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• 1996

Iododeoxyuridine의 유사체인 Iodine-131-5-Iodo-2'-O-methyluridine을 합성하여 종양세포의 증식을 영상화하고자 하였다. 2'-O-methyluridine을 이용하여 Iodine-131-Iodomethyluridine을 요오드발생 반응(Iodogen reaction)으로 간편하게 합성하였고 이를 이용한 자가방사영상과 핵의학영상에서 종양세포의 증식을 영상화 할 수 있었다. 이상의 결과는 Iodine-131-Iodomethyluridine을 이용하여 종양세포의 증식을 감마카메라로 영상화하여 세포증식이 활발한 생존 종양조직이나 재발을 평가할 수 있는 가능성이 있음을 시사한다.

• 대한핵의학회지
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• 제26권1호
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• pp.1-7
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• 1992

저자는 1991년 1월부터 동년 8월 사이에 부산대학교 병원 내과 외래에서 임상증상, 이학적 소견 및 각종 검사소견과 병리조직학적으로 진단된 단순 증식성 갑상선종 환자 20예, 갑상선선종 환자 9예 및 갑상선암환자 20예와 건강대조군 11례에서 말초혈 림프구의 PNP활성을 측정하고 $CD4^+$ 및 $CD8^+$ 세포를 동시에 검색하여 분석할 성적을 다음과 같이 요약한다. 1) 말초혈 림프구의 PNP 활성은 건강 대조군 및 단순 증식성 갑상선종 보다 갑상선선종 및 암환자에서 의의있게 증가하거나 증가하는 경향이 있었다. 2) 말초혈의 $CD8^+$ 세포 비율은 갑상선암환자에서 건강 대조군, 단순 증식성 갑상선종 및 갑상선선종환자 보다 각각 의의 있게 감소하거나 감소하는 경 향이 있었다. 3) 말초혈의 CD4/CD8비는 갑상선암환자에서 건강 대조군, 단순 증식성 갑상선종 및 갑상선선종환자보다 각각 의의 있게 증가하거나 증가하는 경향이 있었다. 이상의 결과에 의하면 갑상선암환자에서는 말초혈의 억제/세포상해 T 세포의 감소에 의한 세포성 면역능의 이상이 있고, 말초혈 림프구의 PNP활성의 측정은 갑상선종양환자의 면역 상태를 파악하는데 도움이 되는 검사라고 생각된다.